1. Hunan Provincial Key Laboratory of Two‐Dimensional Materials and State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China
2. State Key Laboratory for Mesoscopic Physics Frontiers Science Center for Nano‐optoelectronics School of Physics Peking University Beijing 100871 P. R. China
3. Key Laboratory for Micro‐Nano Optoelectronic Devices of Ministry of Education School of Physics and Electronics Hunan University Changsha 410082 P. R. China
4. College of Semiconductors (College of Integrated Circuits) Hunan University Changsha Hunan 410082 P. R. China